Selectively operating ink supply systems are known and have been previously proposed--see, for example, German Patent DE No. 27 03 424 to which U.S. Pat. No. 4,129,077, Fischer, assigned to the assignee of this application, corresponds, which describes an inking system for offset printing machines permitting intermittent or continuous ink film supply. A lifting roller is controlled to operate, intermittently, between an ink ductor roller and a transfer roller when in the intermittent ink supply operating mode. In order to provide for continuous ink film transfer, the ductor roller is positioned to be directly engaged with the ink transfer roller, the lifter roller remaining in continuous permanent engagement with the ductor roller and operating as an idler.
Ink ductor rollers, as well as other rollers in the inking system which are part of the ink distribution arrangement, frequently have a surface which is other than smooth, that is, is stippled, knurled, or formed with minute depressions to better receive and transmit ink. Engagement of such rollers causes difficulties at the surfaces thereof.